Porsche CR 210 radio problem in 1998 993

[p911dad]

Lately, once the radio is warmed up, the right rear channel speaker will intermittently crackle. I switched out the rear speakers, but the result is the right rear still crackles. I then moved the fade to 100% forward position, but it still crackled. So, I unhooked both rears, left it in the forward fade position and no more crackle (obviously the rears are unhooked so they can't crackle, but the fronts are fine). What could be the cause of this? Any suggestions? The radio is original 1998 issue. The system has a JL Audio amp and a Sony 10 CD player added in 2007.

[p911dad]

I pulled the radio, disconnected all the plugs and connections. I put it back together again and it works perfectly. It must have had a little corrosion on the terminals.

[Fever]

Dielectric grease works good on all connections, try it.

[Rickness]

I thought my right front had the same problem, no bass, and distortion. found a used amp for under seat after replacing all three speakers plus rear right side. still same. removed radio from dash, re inserted all plugs and voila,... its working

[p911dad]

Rickness, after my initial success, it started popping and crackling again big time. It looks like it is the amplifier, capacitors gone bad. So, it's out for rebuilding and I'm sending the head unit off to Becker USA for refurbishing. Fingers crossed.